117 



looking at a man's face. In neither instance, perhaps, 

 could the basis of the opinion, which possibly shall 

 approach very close to correctness, be accurately 

 stated. Proof, as to the evidence upon which a 

 conclusion is in such cases based, cannot be antici- 

 pated, and to the inquiry how they were able to 

 tell the age, each would probably answer, by the 

 " looks," but neither would be capable of precisely 

 defining in what these " looks " consisted. 



56. At thirty years old, the jaws are contracted; 

 the lower are not seen when the upper teeth are in 

 view. The coloured engraving, which at first sight 

 seems to suggest that the animal possessed only a 

 single jaw, exhibits the mouth as it appears at the 

 thirtieth year. The animal, the mouth of which is 

 here depicted, had a lower jaw with excellent teeth 

 considering its age, but without elevating its head 

 these could not, while the mouth was closed, be seen, 

 or when seen, the view of those in the upper jaw was 

 lost. This peculiarity arises from the teeth having 

 taken a still more horizontal inclination ; they are 

 now crowded together; and, from the irregularity of 

 their wear, may assume the pointed figure indicated 



